Wii and 360 are gonna be really close going worldwide going into this holiday season. If Wii outsells it by 250k in japan, 100k in america, and 100k in others (450k per month on average) through september there will only be a 500k difference. If Nintendo supplies enough Wiis i think they might be even by the end of september. The thing about 360 is that after Halo and GTA are released and a few months pass I can see 360 sales starting to saturate. Of course it will continue to sell, but how many shooters are gonna be released before all the people that like shooters have all bought the 360?

IMO: I'm not too sure of that, because GTAIII and its spinoffs are all based on the same engine. GTAIV will be rebuilt from the ground up, and should offer more of everything - kinda like what GTAIII did for GTAII.

I haven't touched San Andreas because after finishing the original GTAIII I tried Vice City and after about 20 missions it just all felt too similar. San Andreas just felt like too much of a commitment to finish, despite having more of everything to do (honestly, if I wanted to play billiards, I'd buy a billiards sim!). However, with a spanking new engine and more varied gameplay, I could be sucked right back into the Rockstar fold.

I think the same will go for Halo. Some people are just holding out for the next best thing, which unfortunately for all three consoles, haven't really come out - yet. 

The problem is that it won't offer more of everything... where are the planes... where are the big maps... will there be boats... trains ? And some people will wait it for Pc.

I can't predict what happens 2008 or later, really no one can, but for 2007, and expecially for the upcoming holiday season, I think Nintendo will own the market. The 360 and PS3 both have a casual gamer problem, in that casual gamers don't want to buy their system; they're not even concidering it. I think it's a mistake to compare the Wii's lineup to the 360's lineup and try to make sales predictions off of that. The Wii's best system seller from now till the day it dies will be it's controller. Sure games will matter, but no Wii game is going to have the sales impact for that system that Halo 3 will have on the 360, and really no game will have to. And the best system selling game the system will ever have is probably already out: it's called Wii Sports.

The Wii will pass the 360 as soon as Smashbros. Brawl comes out. Brawl will have a huge attachment rate and sell many more Wii systems. Also Brawl is going to require the user use a the classic controller not the wii-mote/nun-chuck combo. So Nintendo will finally have a standard controller with all the system in the world too.